Expanding underreamer



June 30, 1&31, .r J, QA 1,812,044

' Y EXPANDING UNDERREAMER Filed July 31, 1928 3 Shegts-Sheet l J. GRANT 1,

EXPANDING UNDERREAMER 7 Filed July 31,1928 3 Sheets-Sheet 2 war/ray.

June 30, 1931. J. GRANT EXPANDING UNDERREAMER Filed July 51, 1928 s Sheets-Sheet a Patented June 30, 1931 UNITED STATE .romv sum, or Los enemas, CALIFORNIA nxrmrive ulna-mama Application filed m :1,

not necessarily limited to, the utilization of roller cutters; of simple and strong'design, acting to expand by relative upward move-.

ment of the cutters, and preferably expanding the upper ends of the cutters only. In the preferred forms illustrated-and described herein the rollers move upwardly and at the same time rock outwardly at their upper ends; so that in these designs the cutters rock outwardly for expansion and do so by virtue of upward longitudinal movement. Such upward longitudinal movement is impelled by a spring or springs acting on the lower ends of the cutters and is also impelled and forced by the contact of the cutters with the walls of the hole being reamed,-so that the expansionis forcible and positive. Several different forms, with variations in detail of design, are shownin the accompanying drawings and explained in the following specification. Various other objects 'andcorresponding accomplishments of the invention will be understood from the following detailed description, reference for that pur-.

pose being had to the accompanying drawings, in which:

Figural is a view, partly-in elevation and partly in central longitudinal section, showing one form of the reamer in expanded condition;

Fig. 2 is a similar view showing the reamer of Fig. 1 in contracted position;

Fig. 3 is a cross-section on line 33 of Fig. 1;

ig. 4 is a cross-section on line 4-4 of Fig. 1; V

Fig. 5 is a cross section on line 5-5 of Fig. 1; v

Fig. 6 and 7 are fragmentary longitudinal sections showing a slightly modified' form which gives some expansion at the lower end of each roller as wellas at the upper end;

Fig. S-is a central longitudinal section of a modified form of reamer, in which the exthese slots 31 are shown. as in Fig. 5, as not 1928. Serial No. 296,597.

pansion at the upper end of the rollers is effected by 'a somewhat different mechanism and a single spring operates on all of the rollers, Fig. 8', showing the reamer in expanded position; I A

Fig. 9 is a similar view showing the re amer of Fig. 8*in contracted position;

Figs. 10, 11 and 12 are cross-sections on lines 10-10 of Fig. 9 and lines 11-11 and 12-12 of Fig. 8, respectively;

Fig. 13 is a central longitudinal section of another modified form, utilizing the upper means of expansion of Fig. 1, but actuating all the cutters with a single actuating spring and also providing inward bearings for the 65 cutters intermediate their lengths;

Fig.14 is a similar view showing the reamer of Fig. 13 in expanded condition; and

Figs. 15, 16, and 17 are cross-sections on lines 15--15, 1616, and 17 -17, respectively, of Fig. 13. Referring first to Figs. 1 to 5, I show therein a body 20 having at its upperend the usual screw-threaded pin 21 for connection with a drillstem and at its lower end the usual screw-threaded box 22 for connection with a drill bit 23. The body has the usual water course 24 extending longitudinally through it to carry water to the drill bit below. In the design shown in Fig. 1 this water course is extended through the body by a tube or pipe 25 which, as it is stationary, may be regarded as part of the bod Figs. 13 and following, show a form 1n which the art corresponding to the tube or pipe 25 is ormed as a part of or integral with the body.

The design shown in Figs. 1 to 5 is shown as carrying two roller cutters 30; and for that number of cutters the body is provided. with two opposite cutter receiving slots or recesses 31. In fact these two slots 31, in the form of Figs. 1 to 5. reach clear through the body and virtually-form a single slot where the cutters are located. In their lower parts reaching clear through the body and as thus forming two separate slots. In the lower end of these slots' 31 two blocks 33 are mount 1 ed, the blocks fitting the slots and being held-. 5

in place by some suitable'means. Forin-i stance an internally threaded sleeve 35 may by' screw-threaded upwardly onto the body and shoulder on the body at its upper end, as at 35a, and also screw-threadedly engage the outer edge surfaces of blocks 33; sothat the blocks are not only held in but are also held down by this sleeve. By removing the sleeve the blocks may be moved directly out wardly; and as these blocks carry the lower ends of the cutters, or the lower ends of the cutterv pins, their outward movement also moves the lower ends of the cutters outwardly; and as soon as thelower ends of the cutters are out of the body slots, then the cutters may be moved downwardly and clear of the body.

In the form shown in Figs. 1 to 5 there is an individual spring rovided for each cutter. These springs 3 are mounted in the blocks 33 below the lower ends of the cutter pins. In the form of Figs. 1 to 5 the roller cutters 30 are shown as having central axis pins which may either be integral with the cutters or upon which the cutters may rotate. In either case the cutters may be said to have an upper axis pin end 38 and a lower axis pin end 39. The lower axis pin 39 extends down loosely into a bore 40 in the corresponding block 33 and spring 37 is contained in the bore below the pin 39; a bearing disk 41 being interposed between the spring and the lower end of the pin.

The upper cutter pin 38 is adapted to rest in the recess which extends upwardlyinto the body above the upper end of the cutterreceiving slot 31. These recesses may best be described, in the specific form here shown, as composed of two circular and upwardly extending holes 45 and 46, the hole 45 being deeper or extending further upwardly than the hole 46, and being located further from the central axis of the tool than is the hole 46, and the hole 46 running into the hole 45. Or the whole recess may be described as being one that has a major outer portion 45 with an inner wall 45a against which the cutter pin 38 bears inwardly when the cutter is in expanded position; and having, inward of that wall 45a, an upwardly and outwardly sloping recess wall 46a against which the upper conical end of the cutter pin 38 bears upwardly under the pressure of the spring 37. The diagonal wall=46a has the effect, as the cutter is pushed up by spring 37, of causing the upper end of the cutter to move outwardly as it moves upwardly, and causing the upper cutter pin 38 to be guided outwardly and upwardly into the recess part 45. Or the whole recess may be described generally as being a recess deeper (extending up-. wardly further) in its outer than in its inner part, andhaving an upward and outward diagonally extending wall in its inner part.

From a consideration of the nature of the recess that takes the upper eutter'pin, the action of expansion and contraction of the cutters will be readily understood. The contracted position, as shown in Fig. 2, is the position in which the tool is lowered through the well pipe or casing. Upon reaching point below the pipe or casing the springs tend to move the cutters upwardly, and therefore outwardly at their upper ends, and as soon as the cutters have come into contact with the walls of the hole being reamed, then by such forcible contact the cutters are worked upwardly, and therefore outwardly,

on the body as the body is lowered or as the lvoveglght of the drill stem is applied to the In Figs. 6 and 7 a slight variation is shown, wherein the lower cutter pins are shown as provided with reduced portions 39aimmediately under the cutters 30, so that the pins have heads 39?) at their lower ends. These heads fit the block bores 40 fairly snugly when the cutters are in their upper expanded positions. When the cutters are moved down these heads move down into the enlarged parts 40a of the block bones, and thus the lower ends of the cuttersmay, in the contracted position as shown in Fig. 7, move inwardly. Thus, although the eontractive and expansive movement at the lower ends of the roller cutters may or may not be as much as the corresponding movement at the upper ends of the cutters, the cutters of Figs. 6 and 7 have contractive and expansive movement at their lower as well as at their upper ends. In these figures the expansive movement at the lower ends is shown as being somewhat less than at the upper ends, so that the cutters still have an outwardly rocking movement at their'upper ends.

In Figs. 8 to 12 .a modification is shown wherein a single cutter actuating spring 370 moves all the cutters, which are here shown as three in number. The body 200 is provided with three cutter-receiving slots 310. Spring 370 is here shown as resting at its lower end on the pin 230 of the drill bit, and a cutter propeller 50 plays vertically in bore 51 which forms the spring chamber. This cutter propeller has at its upperend aspider 52 whose arms project out through the slots 31a, and the lower end of a roller cutter 300 is mounted on each spider arm. Each spider arm carries a block 53 of the configuration best shown in Fig. 11. These blocks have lateral extensions 53a at their outer ends which overlie the outer surface of the body; they thus hear back against the body and also bear back against the shoulders indicated at 535 on the spider 52. And they each have a laterally extending lug 530 which extends laterally into an adjacent body slot 310 so as to hold each block inwardly. These blocks are made of suitable material to form up-thrust bearing surfaces for the lower ends ol' the rollers; and the lower roller pins 390 are mounted somewhat loosely in bores which extend through the blocks 53' and through the arms of the propeller. The pins and rollers are held down to the propeller by any suitable means that allows rotation of the 'pins and rollers (therolle'rs being'here shown as integral with the pins), as by dowelpins 55 which engage in annular grooves 39d in pins 390.

Instead of the upper ends of the rollers being provided with up er pins which play in recesses in the body, t e arrangement here is relatively reversed; the rollers being provided with recesses 45.0 in their upper ends and the body being provided with downwardly extending studs 38c. Recesses 450 in the upper ends of the rollers are here shown as plain cylindric bores with a conical'fiare upper conical bearing faces. d bear upor counter sink 45d at the upper end. Each stud 380 is carried by .a bearing plate 38d, these plates having cone bearing faces 38e and 38h surrounding the bases of the studs 380. When the rollers are in their upper expanded positions as shown in Fig. 8 their wardly and laterally on the conical bearing faces 38a and 38k; and their recess bores 45c bear radially on the cylindric parts of studs 38c. The'lower end of each stud is partially cut away at the outer side, as shown at 38;, so that the rollers when in their lower positions, as shown in Fig. 9'may move inwardlyto collapsed position at their upper ends, tilting inwardly at their u per ends for collapse and tilting outward y at their upper ends for expansion. An angular or beveled expanding face 38g, at the upper end of the cut away ortion 38; on the stud, causes the outward tilting movement of the upper end of the roller when the roller. is moved upwardly under the action of spring 37 c or by contact with the walls of the hole.

Fig. 13 and following show another form which embodies the specific mode of expansion heretofore explained in connection with the form of Fig. 1, but also embodies actuation by a single spring, and further includes provision of an intermediate bearing for each cutter. In the form here shown the body 20m is provided with two opposite cutterreceiving slots 31m which do not extend clear through the body, except at their lower ends (see Fig.1?) where the cutter propeller plate 50m rests on top of cutter actuating spring 37m and extends across-the interior of the body. Thus, in the center of the body back of the cutters there remains an integral web through which the watercourse 24 extends, and which web is utilized as a central-back-bearing abutment for the central portion of the cuttersor for the cutters at some point below their upper ends. Roller cutters 30m are here shown, as mounted on ins 38m, the upper ends of which exten into recesses 45, 46 the same as those previously explained in connection with Fig.

1. The lower ends of these pins, as shown at 39m, extend loosely down through bores 40m in blocks 33m, which blocks are constructed and mounted in the body in much the same'manner as has been explained in connection with Fig. 1, a sleeve 35m being used for that purpose. The lower ends 39m ofthe roller 'pins rest on the propeller plate 501% and the spring pushing upwardly on the propeller plate pushes theroller pins upwardly. The ro ler pins may either be integral with or separate pieces from the rollers; but for convenience of assembly the are here shown as separate, the rollers eing mounted on the pins. The rollers may either rotate on the pins as bearings or they may be tightly fitted on the pins which will then rotate with the rollers. The rollers are shown as divided into two parts and a bearing block is mounted on each roller pin between the roller parts 30m. These bearing blocks 65 fit the body slots 31m and bear back against the. central web 60. And the central web is faces when the cutters move up and out to 'provided at its opposite faces with inclined expanded position, the bearing blocks in final expanded position bear back firmly against the central web to support the intermediate parts of the cutters against inward thrusts. Thus in this form the cutters are given a strong support against inward thrusts-1directly on the body and at points below their upper ends.

I claim:

1. An expansive reamer, comprising the combination of a vertically slotted body, avertically extending cutter located in the body slot, mounting means for the lower end of the cutter'on the body allowing vertical movement and oscillatory movement of the cutter, coacting means on the body and on the upper end of the cutter acting to causeoutward tilting movement of the upper end of the cutter upon upward movement thereof. and a back bearing for the cutter intermediate its ends inwardly against the body.

2. In an expansive reamer, the combina-- tion of a body, avertically extending cutter element associated with the body, mounting means for the lower end of the cutter element allowing vertical movement and lateral tilt-' ing movement of the cutter element, coacting means with the body and upper end of the cutter element to cause outward tilting movement of the upper end of the cuttere'lement by virtue of upward longitudinal movement thereof, and'a back bearing for the cutter intermediate its ends inwardly against the body.

3. In an expansive reamer, the combination of a body, a vertically extending cutter element associated with the body, mounting means for" the lower end of the cutter element allowing vertical movement and lateral tiltter supporting block situated in the lower ing movement oi the cutter element, coacting means on the body and upper end of the cuttor element to cause outward tilting movement of the upper end of the cutter element by virtue of upward longitudinal .niovement thereof, said last mentioned means comprising a pin and a recess, one of which is provided with an upwardly and outwardly extending diagonally expanding surface, and a back bearing for the cutter intermediate its ends inwardly against the body.

4. An expansive reamer comprising in combination a vertically slotted body, a cut tor supporting block situated in the lower part of the body slot, a roller cutter having an axis pin the lower end of which is mounted in said block to allow vertical movement and lateral tilting movement of the cutter, a spring acting upon the lower end of the cutter axis pin to move the cutter upwardly, and co acting means on the upper end of the roller cutter and the body acting to cause outward tilting movement of the upper end of the cutter upon upward movement thereof.

5. An expansive reamer comprising in combination a vertically slotted body, a cut part of the body slot, a roller cutter having an axis pin the lower end of which is mounted in said block to allow vertical movement and lateral tilting movement of the cutter, and coacting means on the u per end of the roller cutter and the body acting to cause outward tilting movement of the upper end of the cutter upon upward movement thereof, said means comprising a coacting pin and recess one of which is provided with an upwardly and outwardly extending diagonal surface.

6. An expansive reamer comprising in combination a vertically slotted body, a cutter supporting block situated in the lower part of the body slot, a roller cutter having an axis pin the lower end of which is mounted in said block to allow vertical movement and lateral tilting movement of the cutter, and coacting means on the upper end of the roller cutter and the body acting to cause outward tilting I movement of the upper end of the cutter upon upward movement thereof, said means comprising a recess in'the body extending upwardly above the upper end of the body slot, said recess having at its inner side an 11 wardly and outwardl extending diagonal y expanding wall, and t e upper end of the cutter axis pin extending intosaid recess.

7. An expansive reamer comprising in combination a vertically slotted body, a cutter supporting block situated in the lower part or the body slot, a roller cutter having an axis pin the lower end of which is mounted in said block to allow vertical movement and lateral tilting movement of the cutter, coacting means on the upper end of the roller cutter and the body acting to cause outward tilting move-- eiaoee ward movement thereof, and a back bearing for the cutter intermediate its ends inwardl against the body.

8. n expansive reamer comprising in combination a vertically slotted body, a cutter supporting block situated in the lower part of the body slot, a roller cutter having an axis pin the lower end of which is mounted in said block: allow vertical movement and lateral tilting movement oic the cutter, and coacting means on the 11 per end of the roller cutter and the body acting to cause outward tilting movement of the upper end of the cutter upon upward movement thereof, said means comprising -a recess in the body extending upwardly above the upper end of the body slot, said recess having at its inner side an upwardly and outwardly extending diagonally expanding wall, and the upper end of the cutter axis pin extending into said recess, and a back bearing for the cutter intprmediate its ends inwardly against the 9. An expansive reamer comprising in combination a vertically slotted body, a cutter supporting block situated in the lower part of the body slot, a roller cutter having an axis pin the lower end of which is mounted in said block to allow vertical movement and lateral tilting movement of the cutter, and coacting means on the upper end of the roller cutter and the body acting to cause outward tilting movement of the upper end of the cutter upon upward movement thereof, the body having an interior webinward of the body slot and a bearing block mounted on the cutter intermediate its ends and bearingback' against the surface of said interior body web.

10. An expansive reamer comprising in combination a vertically slotted body, a cut ter supporting block situated in the lower part of the body slot, a roller cutter having extending upwardly above the upper end of the body slot, said recess having at its inner side an 11 wardly and outwardly extending diagonal y expanding wall, and the upper end of the cutter axis pin extending into said recess, the body having an interior web inward of the body slot and a bearing block mounted on the cutter intermediate its ends and bearing back against the surface of said interior body web.

11. In an expansive reamer, the combination of a body, a vertically extending cutter element mounted on the body and movable vertically longitudinally of the body, bearings for the upper and lower ends of the cutter element on the body, a back bearing for the cutter elementintermediate its ends inwardly inst the body, and said bearings being so ormed that upward relative movement of the element causes its outward expansive movement.

12. An expansive reamer comprising in combination a vertically slotted body, a cutter supporting'block situated in the lower part of the body slot, a roller cutter hav-,

mg an axis pin the lower end of which is mounted in said block to allow vertical movement and lateral tilting movement .of the cutter, and coactingmeans on the upper end of the roller cutter and the body acting to cause outward tilting movement of the upper end of the cutter upon upward movement thereof. Inwitness that claim the foregoing I have hereunto subscribed my name this 2d day of July, 1928. JOHN GRANT. 

